Python: Exception Handling

Python provides a robust mechanism for handling errors, known as exception handling. In this article, we will explore the concept of exception handling in Python and how it can improve your code’s robustness and user experience.

Rahul S


In Python, an exception is an event that disrupts the normal flow of a program’s execution. Exceptions can occur for various reasons, such as attempting to divide by zero, accessing a non-existent file, or trying to convert an invalid data type. When an exception occurs, the program typically terminates, which can be frustrating for users.

To illustrate this, let’s consider a simple example:

X = 10 / 0  # Attempting to divide by zero

Executing this code will result in a “ZeroDivisionError” and will terminate the program. This abrupt termination is not user-friendly and can be avoided with exception handling.

Using try and except

Exception handling in Python revolves around the try and except blocks.

The try block contains the code that might raise an exception. If an exception occurs within the try block, the program doesn't crash immediately. Instead, it transfers control to the nearest except block, allowing you to handle the error gracefully.

Here’s how you can use try and except to handle a "ZeroDivisionError":

X = 10 / 0 # Attempting to divide by zero
except ZeroDivisionError:
print("You can't divide by zero.")

In this modified code, we enclose the potentially problematic code within the try block. If a "ZeroDivisionError" occurs, the program jumps to the except block and executes the code inside, which prints a user-friendly error message.

Handling Multiple Exceptions

In more complex scenarios, you may encounter multiple types of exceptions within the same try block. To handle different exceptions differently, you can use multiple except blocks.

For example, consider a situation where the user provides input, and you want to handle both "ValueError"…